Abstract: An imaging system includes a roller that conveys a printing medium, a medium sensor that detects a medium property of the printing medium conveyed by the roller, and a controller that adjusts a conveyance speed of the printing medium by the roller based on the medium property detected by the medium sensor.

Abstract: An optical media sensor includes a guide wall, a light emitter, a light receiver and a blower. The guide wall has an opening. The light emitter emits light to a medium sheet through the opening. The light receiver detects an amount of light travelling from the medium sheet. The blower generates a wind pressure that presses the medium sheet against the guide wall when detecting the amount of light.

Abstract: An imaging system includes: a housing; an ionizer including a first electrode and a second electrode and to charge airborne particles contained in the housing; a particle filter collecting charged particles; and a controller changing an amount of a current flowing between the first electrode and the second electrode by electric discharge during a printing operation, in which the controller controls the amount of current based on a print state indicator associated with the printing operation.

Abstract: A water content sensor for a recording medium includes a single light emitting part, a wavelength separation device and a detector device. The single light emitting part emits infrared light in a wavelength range including an absorption wavelength of water along one incident light path toward the recording medium. The wavelength separation device separates infrared light, either reflected from or transmitted through the recording medium, into a first light in a first wavelength range including the absorption wavelength of water and a second light in a second wavelength range excluding the first wavelength range. The detector device receives the first light in the first wavelength range and the second light in the second wavelength range, and generates a first output corresponding to an intensity of the first light received and a second output corresponding to an intensity of the second light received, respectively.

Abstract: An imaging system includes a roller that conveys a printing medium, a medium sensor that detects a medium property of the printing medium conveyed by the roller, and a controller that adjusts a conveyance speed of the printing medium by the roller based on the medium property detected by the medium sensor.

Abstract: A constant current driving circuit includes a control integrated circuit which generates a switching signal, a switching device which switches an input power supply voltage based on the switching signal, a rectifying diode which rectifies a current of the input power supply voltage, a smoothing inductor which smoothes the current of the input power supply voltage, and a smoothing condenser which outputs an output current. The control integrated circuit includes a reference signal generator which generates a reference signal having information about a target constant current, a comparator which compares the current of the input power supply voltage with the reference signal, a flip-flop circuit which outputs a flip-flop signal having information about a time period during which a set state is maintained, and a delay circuit which outputs the switching signal to the switching device based on the flip-flop signal to control the switching device.

Abstract: A constant current driving circuit includes a control integrated circuit which generates a switching signal, a switching device which switches an input power supply voltage based on the switching signal, a rectifying diode which rectifies a current of the input power supply voltage, a smoothing inductor which smoothes the current of the input power supply voltage, and a smoothing condenser which outputs an output current. The control integrated circuit includes a reference signal generator which generates a reference signal having information about a target constant current, a comparator which compares the current of the input power supply voltage with the reference signal, a flip-flop circuit which outputs a flip-flop signal having information about a time period during which a set state is maintained, and a delay circuit which outputs the switching signal to the switching device based on the flip-flop signal to control the switching device.

Abstract: Provided is a light source driver which drives a light source including a switch unit which selects a light source; a chopper circuit which supplies power from an inductor to a light emitting diode (LED) via a diode in an on-state of a field effect transistor (FET), where the power accumulates in the inductor in the on-state of the FET; an oscillator which outputs a signal such that power is supplied to the LED through the chopper circuit, wherein the power changes according to the inductance of the inductor and the load capacity of the LED selected; and a chopper circuit driving unit which operates the FET in response to a signal whose duty ratio is the same as that used to supply power to the selected LED according to the load capacity of the LED and whose switching frequency is the same as a signal output from the oscillator.

Abstract: An LED illumination unit, a projection display device using the LED illumination unit, and a method of operating the LED illumination unit are provided. The LED illumination unit includes a light source with a plurality of LEDs, and a lighting control unit which sequentially turns on the LEDs for lighting time sections which are assigned for each LED in a cyclic time period. The lighting control unit includes a driving signal modulator which generates a modulation signal for turning on at least one of the LEDs with a lighting duty that is shorter than the lighting time section for the at least one of the LEDs. The method includes sequentially turning on a plurality of LEDs of the LED illumination unit for lighting time sections which are assigned for each LED in a cyclic time period. At least one of the LEDs is turned on with a lighting duty that is shorter than its lighting time section.

Abstract: An image display apparatus includes a light source unit including light emitting elements halving different wavelengths, wherein n (n is an integer higher that 2) light emitting elements have at least one wavelength; and a light-up controller which drives the light emitting elements having different wavelengths in a time-sequential manner within a time period, wherein the light-up controller divides the n light emitting elements having at least one wavelength into m (m is an integer satisfying 2?m?n) light-up groups having a same light-up timing, and the m light-up groups are alternately lighted at a frequency of 1/m within the time period, so that any one of the m light-up groups can be lighted within the time period.